Department of Chemistry, National Taiwan Normal University, Taipei, 116, ROC, Taiwan.
Chemistry. 2010 Jun 18;16(23):7030-8. doi: 10.1002/chem.201000483.
Practical and convenient synthetic routes have been developed for the synthesis of a new class of pyrrolidinyl-camphor derivatives (7 a-h). These novel compounds were screened as catalysts for the direct Michael addition of symmetrical alpha,alpha-disubstituted aldehydes to beta-nitroalkenes. When this asymmetric transformation was catalyzed by organocatalyst 7 f, the desired Michael adducts were obtained in high chemical yields, with high to excellent stereoselectivities (up to 98:2 diastereomeric ratio (d.r.) and 99 % enantiomeric excess (ee)). The scope of the catalytic system was expanded to encompass various aldehydes and ketones as the donor sources. The synthetic application was demonstrated by the synthesis of a tetrasubstituted-cyclohexane derivative from (S)-citronellal, with high stereoselectivity.
已经开发出了实用且方便的合成路线，用于合成一类新的吡咯烷基莰烷衍生物（7a-h）。这些新型化合物被筛选为不对称迈克尔加成反应的催化剂，用于催化对称的α,α-二取代醛与β-硝基烯烃的直接迈克尔加成反应。当不对称转化由有机催化剂 7f 催化时，所需的迈克尔加成产物以高化学收率、高至优异的立体选择性（高达 98:2 非对映体比率（d.r.）和 99%对映体过量（ee））获得。催化体系的范围扩大到包括各种醛和酮作为供体来源。通过（S）-香茅醛与合成的四取代环己烷衍生物的合成，展示了其合成应用，具有高的立体选择性。
